1. Field of the Invention
This invention relates to reference information included in captured digital signals, and more specifically to a digital reference information providing a baseline for determining and measuring audio and video signal changes in the post production and display processes.
2. Description of the Prior Art
The move to capture images electronically for cinema productions closely resemble the evolution of television production moving from film to video based capture technologies. Tools developed for both film and video provided the post production processes the ability to restore the original look of the scene by using various tools and procedures. For the film production, a color chart was photographed at the head of each scene to assist in color balance during the film to tape transfer. Video productions may use a color bar reference at the head of the program material to assist in proper set-up of playback levels. Both systems may work for the intended media.
Unlike film, an electronic camera offers the ability to see the result immediately on a picture monitor. Observing recent productions, set lighting and aperture were adjusted based on the image that was displayed on a waveform and picture monitor near the camera. Upon being satisfied that the scene was “correct”, the production would proceed and the image recorded on a High Definition Tape recorder. What may be important to the director and cinematographer as far as subtle detail in the shadows and lace curtains in a window may be overlooked in later steps of postproduction. Rarely will both detail in shadows, and detail in backlit windows survive together, either one or the other are normally clipped during the post process. But what is needed is test signal data that may reside along with the active picture and or sound data that may identify benchmark image or sound characteristics.